What causes a stroke?

A stroke is primarily caused by a disruption in the flow of blood to the brain, which can occur due to a blood clot. When a blood clot forms in one of the arteries leading to the brain or in a blood vessel within the brain itself, it obstructs the blood supply, resulting in the affected brain tissue becoming deprived of oxygen and nutrients. This can cause significant damage to the brain cells and lead to the symptoms associated with a stroke.

It’s important to recognize that while there are other medical conditions that can affect blood pressure or overall cardiovascular health, they do not directly cause a stroke in the same way that a blood clot does. For example, a sudden drop in blood pressure could lead to fainting or other complications but is not a direct cause of a stroke. Similarly, an increase in blood flow to the heart is more related to cardiovascular health rather than an acute event like a stroke. A severe headache, while it can be a symptom of certain types of strokes, especially migraines or hemorrhagic strokes, does not independently cause a stroke. Therefore, the presence of a blood clot is the most direct and primary cause of a stroke, making it the correct answer in this context.